/Engine/Plugins/Runtime/MeshModelingToolset/Source/ModelingComponents/Public/Drawing/PolyEditPreviewMesh.h
Make a hit-target mesh that is an infinite extrusion along extrude direction. If bUseNormalDirection, use per-vertex normals instead
void MakeExtrudeTypeHitTargetMesh ( [FDynamicMesh3](API\Runtime\GeometryCore\DynamicMesh\FDynamicMesh3) & TargetMesh, bool bUseNormalDirection )